Originally posted by Al Stein
...
I can make them rotate evenly throughout their travel... which is what I know a lot of models do, but that makes them fairly draggy, even at fairly low deflection angles, so I wouldn't get maximum bennefit for takeoffs.
...
.
The first motion on the Fowler flap is to extend the wing area, not make a flap per se.. Most commercial planes will use this first motion with a slight amount of deflection for takeoff. On the Tristar, takeoff flap is 10 degrees. Lots of rearward motion, little down deflection.
Landing flaps, OTOH, are 33 degrees (CAA cert) or 42 degrees (FAA cert). Lots of down deflection after the 10 degree position to add -drag-, not lift!
Doing this on a model can be intricate as the parts are small and easily jammed.
A Youngman (Fairey Firefly) style flap might be more easily mechanized on a model.